Changes in biomechanics of skiing at maximal velocity caused by simulated 20-km skiing race using V2 skating technique.

This study investigated how the fatigue caused by a 20-km simulated skating cross-country skiing race on snow affects the final spurt performance from a biomechanical perspective. Subjects performed a 100-m maximal skiing trial before and at the end of the simulated race. Cycle characteristics, ground reaction forces from skis and poles, and muscle activity from eight muscles were recorded during each trial. Results showed that subjects were in a fatigued state after the simulated race manifested by 11.6% lower skiing speed (P<.01). The lower skiing speed was related to an 8.0% decrease in cycle rate (P<.01), whereas cycle length was slightly decreased (tendency). In temporal patterns, relative kick time was increased (10.9%, P<.01) while relative poling time was slightly decreased (tendency). Vertical ski force production decreased by 8.3% while pole force production decreased by 26.0% (both, P<.01). Muscle activation was generally decreased in upper (39.2%) and lower body (30.7%) (both, P<.01). Together these findings show different responses to fatigue in the upper and lower body. In ski forces, fatigue was observed via longer force production times while force production levels decreased only slightly. Pole forces showed equal force production times in the fatigued state while force production level decreased threefold compared to the ski forces.

Semiautomated quantitative image analysis of glomerular immunohistochemistry markers desmin, vimentin, podocin, synaptopodin and WT-1 in acute and chronic rat kidney disease models.

Five different glomerular immunohistochemistry markers were evaluated and compared in four different acute and chronic rat kidney disease models. Progression of glomerular or podocyte damage was shown in the puromycin aminonucleoside nephrosis (PAN) and Zucker fatty/spontaneously hypertensive heart failure F1 hybrid (ZSF1) rat model. Progression and prevention of glomerular damage was demonstrated in the Zucker diabetic fatty (ZDF) and Dahl salt-sensitive (Dahl SS) rat. Immunohistochemistry was performed for desmin, vimentin, podocin, synaptopodin and Wilms tumor protein-1 (WT-1), and evaluation of glomerular immunohistochemistry markers was done by semiautomated quantitative image analysis. We found desmin and WT-1 as the most sensitive markers for podocyte damage in both acute and chronic glomerular damage followed by vimentin, podocin and synaptopodin. We were able to demonstrate that early podocyte damage as shown by increased desmin and vimentin staining together with either a phenotypic podocyte change or podocyte loss (reduced numbers of WT-1-stained podocytes) drives the progression of glomerular damage. This is followed by a reduction in podocyte-specific proteins such as podocin and synaptopodin. Our report describes the different sensitivity of glomerular or podocyte markers and gives future guidance for the selection of the most sensitive markers for efficacy testing of new drugs as well as for the selection of tissue-based toxicity markers for glomerular or podocyte injury. In addition to functional clinical chemistry markers, desmin and WT-1 immunohistochemistry offers reliable and valuable data on the morphologic state of podocytes.

Architecture of the maize mitochondrial atp1 promoter as determined by linker-scanning and point mutagenesis.

Plant mitochondrial promoters are poorly conserved but generally share a loose consensus sequence spanning approximately 17 nucleotides. Using a homologous in vitro transcription system, we have previously shown that an 11-nucleotide sequence within this region comprises at least part of the maize mitochondrial atp1 promoter (W. Rapp and D. Stern, EMBO J. 11:1065-1073, 1992). We have extended this finding by using a series of linker-scanning and point mutations to define the atp1 promoter in detail. Our results show that mutations at positions -12 to +5, relative to the major transcription start site, can decrease initiation rates to between < 10 and 40% of wild-type levels. Some mutations, scattered throughout this region, have lesser effects or no effect. Taken together, our data suggest a model in which the atp1 promoter consists of a central domain extending from -7 to +5 and an upstream domain of 1 to 3 bp that is centered around -11 to -12. Because many mutations within this promoter region are tolerated in vitro, the maize atp1 promoter is distinct from the highly conserved yeast mitochondrial promoters.

Two-Segment Foot Model for the Biomechanical Analysis of Squat.

Squat exercise is acquiring interest in many fields, due to its benefits in improving health and its biomechanical similarities to a wide range of sport motions and the recruitment of many body segments in a single maneuver. Several researches had examined considerable biomechanical aspects of lower limbs during squat, but not without limitations. The main goal of this study focuses on the analysis of the foot contribution during a partial body weight squat, using a two-segment foot model that considers separately the forefoot and the hindfoot. The forefoot and hindfoot are articulated by the midtarsal joint. Five subjects performed a series of three trials, and results were averaged. Joint kinematics and dynamics were obtained using motion capture system, two force plates closed together, and inverse dynamics techniques. The midtarsal joint reached a dorsiflexion peak of 4°. Different strategies between subjects revealed 4° supination and 2.5° pronation of the forefoot. Vertical GRF showed 20% of body weight concentrated on the forefoot and 30% on the hindfoot. The percentages varied during motion, with a peak of 40% on the hindfoot and correspondently 10% on the forefoot, while the traditional model depicted the unique constant 50% value. Ankle peak of plantarflexion moment, power absorption, and power generation was consistent with values estimated by the one-segment model, without statistical significance.

Biomechanics of simulated versus natural cross-country sit skiing.

The purpose of this study was to investigate the biomechanics of cross-country sit-skiing in simulated and natural skiing. Thirteen international level athletes participated in a ski ergometer test (simulated conditions) and a test on snow in a ski-tunnel (natural conditions) using their personal sit-ski. Tests in both conditions were performed at individual maximal speed. When comparing the two conditions the main results were: (1) maximal speed in simulated conditions was lower (p<0.05) but correlated well with the natural condition (r=0.79, p<0.001); (2) no differences in pole force variables were found; peak force (r=0.77, p<0.01) and average force (r=0.78, p<0.01) correlated well; (3) recovery time and time to peak did not differ and time to impact correlated with each other (r=0.88, p<0.01); (4) no differences were found in peak electromyography (EMG) and average EMG for Triceps, Pectoralis, and Erector Spinae; Rectus Abdominis did not differ in peak. EMG peak and average EMG of all muscles were correlated between the two conditions (r=0.65-0.94; p<0.05-0.01). Although some differences were observed, this study demonstrated that technical skill proficiency in natural and simulated cross-country skiing is comparable from a force production and muscle activation perspective.

Purification of human gastric proteases by immunoadsorbents: pepsinogen II-group.

The pepsinogen II group was prepared from gastric mucosal extract by a two-step procedure consisting of immunoadsorption to an anti-pepsinogen II column, followed by ion exchange chromatography on DEAE-Sephadex A-50. The final product was pure according to biochemical and immunochemical criteria. As determined by quantitative immunodiffusion, the enrichment factor of pepsinogen II was 34. A recovery of 55% was calculated. The effectiveness of this procedure was due to the use of purified anti-pepsinogen II antibodies for immunoadsorption. This was achieved by immunoadsorption to Sepharose bound crude pepsinogen and a further passage over an unrelated immunoadsorbent (human serum coupled to Sepharose). The immunoadsorbent prepared using purified anti-pepsinogen antibodies showed low non-biospecific binding of gastric extract proteins. Complete separation of pepsinogen II from pepsinogen I was observed in one single passage. Purified pepsinogen II showed two protein bands in polyacrylamide gel electrophoresis and four bands of proteolytic activity in agarose enzyme electrophoresis. In both methods, as well as in two-dimensional immunoelectrophoresis, components with the same electrophoretic mobility were detected in pure preparations of group and II pepsinogens. Consequently, only in pure preparations was it possible to define the exact number of bands belonging to each of the two groups and to assess the immunological specificity of every band. Upon hydroxyapatite chromatography purified pepsinogen II was further resolved into two fractions.

Purification of human gastric proteases by immunoadsorbents. Pepsinogen I group.

Human pepsinogen I group was purified by immunoadsorption techniques. Gastric mucosal extracts containing the pepsinogen I group and the pepsinogen II group and concentrated urine containing only pepsinogen I group were separated by DEAE-ion-exchange chromatography to remove the bulk of human serum protein. Fractions displaying proteolytic activity were further purified by adsorption on an anti-pepsinogen I group Sepharose immunoadsorbent column. After desorption, gastric pepsinogen I group was separated from pepsinogen II group. Trace amounts of contaminating protein were removed from preparations from gastric mucosal extracts and urine by passage over an anti-human serum immunoadsorbent column. The purity of pepsinogen I group from both sources was assessed by electrophoretic and immunological criteria. The isolated pepsinogen I group from gastric mucosal extracts and urine were by biochemical and immunochemical criteria identical with each other and with the pepsinogen I group in the unfractionated starting materials. By agarose enzyme electrophoresis four bands were detected and it was determined that the proteases of the pepsinogen I group express the same individual antigenic determinant.

Lipopeptide-polyoxyethylene conjugates as mitogens and adjuvants.

Two lipopeptide analogues of the Escherichia coli lipoprotein rendered water-soluble by polyoxyethylene were tested for mitogenicity in vitro in murine and human B lymphocytes and for adjuvant activity in vivo in mice. These highly amphiphilic lipopeptides retained the biological activity other lipopeptides usually exerted which supports the hypothesis of specific interactions of lipopeptides with membranes of reactive cells. The activation of human B lymphocytes by these lipopeptides was much less pronounced compared to that of murine cells. However, given in combination with anti-CD40 antibodies plus interleukin-4, human B lymphocytes could synergistically be stimulated to proliferate. As an adjuvant, the polyoxyethylene linked lipopeptides were almost as potent as Freund's adjuvants and other basic lipopeptides. Being water-soluble, these novel analogues are easy to apply and they are suitable for field studies as adjuvants when sonication can not usually be provided.

Plasma levels and clinical effects of thioridazine and thiothixene.

The effects of thioridazine and thiothixene were studied by a double-blind technique on 40 schizophrenic patients. The doses were adjusted for optimal clinical and therapeutic effects and side effects were rated after three and eight weeks of treatment. No statistically significant differences were observed between the two drugs or between either of the two drugs and the previous medication. Plasma levels were estimated by a fluorometric technique after three and eight weeks of treatment. No correlation was found between plasma levels and clinical effects for either thioridazine or thiothixene. Plasma levels of both drugs were clearly correlated to dosage after three weeks of treatment. After eight weeks this correlation persisted for thioridazine but not for thiothixene. By that time plasma levels of thiothixene had decreased to about 30 per cent of the initial value, indicating strong enzyme induction.

Quantitation of alpha1-acid glycoprotein in neutralized gastric juice by electroradioimmunoassay (ERIA).

Alpha1-Acid glycoprotein (AGP) was quantitated by an electroradioimmunoassay (ERIA) in in vivo neutralized gastric juice (nGJ) of 226 patients, including normals and patients with various gastic diseases. The accuracy of ERIA was tested by extraction and recovery experiments. A possible interference of nGJ constituents with the quantitation procedure was excluded. The mean AGP concentration in gastric juice of normals was 1.04 mu/ml (range 0.04-4.1 mu/ml). The concentration was significantly higher in the gastric cancer group (mean 31.6 mu/ml, p less than 0.01), in the group of chronic metaplastic gastritis (mean 5.7 mu/ml, p less than 0.01) and in the group of BII resections (mean 8.8 mu/ml, p less than 0.05). In 6 out of 12 nGJ samples with high AGP concentrations, a spur formation (Ouchterlony type III) was observed in double gel diffusion when compared to serum AGP. In 3 out of these 12 samples, the dilution curve in ERIA differed from the serum AGP dilution curve. These results indicate a difference in the antigenic properties of AGP in nGJ.

Histological and immunohistological studies on gastric mucosa. I. The presence of CEA in dysplastic surface epithelium.

Surface and foveolar gastric cells (SE) of 74 gastric resection specimens were studied by classical and indirect immunoenzyme histology. Immunoadsorbed CEA-antibodies reacting only with the specific determinant of of the CEA molecule were applied. The following SE types with different CEA distribution patterns were observed: Type SE-O, no CEA, normal neutral mucosubstances (MCS); type SE-A, CEA present in the lower half of the SE, important decrease of MCS, mild cell dysplasia by conventional criteria; type SE-B, CEA present in the total cell, absence of MCS, moderate until marked dysplasia; type SE-C, CEA present or decreased, absence of MCS, very important cell dysplasia resembling cancer cells. CEA proved to be useful as marker for the degree of SE dysplasia.

Toxicologic and teratologic studies of oxibendazole in ruminants and laboratory animals.

Acute toxicity of oxibendazole was assessed with single oral doses given to mice (4 to 32 g/kg of body weight), sheep (230 to 600 mg/kg), and cattle (600 mg/kg); there were no ill effects. Subacute toxicity did not occur with multiple doses given 5 days to cattle (30 to 75 mg/kg/day) and to sheep (10 to 50 mg/kg/day). Chronic effects did not occur with daily doses of 3 to 30 mg/kg given 98 days to rats and dogs. Teratogenicity of the compound was studied in mice, rats, and sheep medicated at a dose level of 30 mg of oxibendazole/kg and in cattle given 75 mg/kg on selected dates during pregnancy. Microscopically, rodent fetuses seemed normal, and on gross physical examination, lambs and calves were free of malformations and ossification variations.

A manufacturer's perspective: Hewlett Packard Y2K action plan.

Medical device manufacturers must ensure that their devices are safe and effective including investigating issues involved with the century rollover. Manufacturers must begin early to evaluate their products in order to allow time to correct and distribute these product corrections and communicate to their customers so they can prepare for the Y2K event.

IBM's Health Analytics and Clinical Decision Support.

OBJECTIVES: This survey explores the role of big data and health analytics developed by IBM in supporting the transformation of healthcare by augmenting evidence-based decision-making. METHODS: Some problems in healthcare and strategies for change are described. It is argued that change requires better decisions, which, in turn, require better use of the many kinds of healthcare information. Analytic resources that address each of the information challenges are described. Examples of the role of each of the resources are given. RESULTS: There are powerful analytic tools that utilize the various kinds of big data in healthcare to help clinicians make more personalized, evidenced-based decisions. Such resources can extract relevant information and provide insights that clinicians can use to make evidence-supported decisions. There are early suggestions that these resources have clinical value. As with all analytic tools, they are limited by the amount and quality of data. CONCLUSION: Big data is an inevitable part of the future of healthcare. There is a compelling need to manage and use big data to make better decisions to support the transformation of healthcare to the personalized, evidence-supported model of the future. Cognitive computing resources are necessary to manage the challenges in employing big data in healthcare. Such tools have been and are being developed. The analytic resources, themselves, do not drive, but support healthcare transformation.